The harbor master shall, whenever he or she may deem it necessary, assign places for all boats, barges, rafts and vessels of whatever kind, giving preference to commercial craft in the order of their arrival, and every person in charge thereof shall cause the same to be moored at or removed to the place assigned therefore; provided, that no boat, barge or raft shall be compelled to leave its assigned place while receiving or discharging cargo.
(1980 Code, § 13.503)